Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Stereospecific dextrorphan tolerance in rats

J M Carney, V L Sirochman

    British Journal of Pharmacology
    |February 1, 1981
    PubMed
    Summary
    This summary is machine-generated.

    Levorphanol is 20 times more potent than dextrorphan in rats. Chronic dextrorphan caused tolerance, but levorphanol did not, suggesting distinct central nervous system (CNS) effects of opioid isomers.

    Related Concept Videos

    You might also read

    Related Articles

    Articles linked to this work by shared authors, journal, and citation graph.

    Sort by
    Same author

    Caloric restriction mimetics: metabolic interventions.

    The journals of gerontology. Series A, Biological sciences and medical sciences·2002
    Same author

    Can HIV-1-contaminated syringes be disinfected? Implications for transmission among injection drug users.

    Journal of acquired immune deficiency syndromes (1999)·2001
    Same author

    Use of bleach to disinfect HIV-1 contaminated syringes.

    American clinical laboratory·2001
    Same author

    Oxidative stress leading to loss of critical proteases in Alzheimer's disease. An alternative view of the etiology of AD.

    Annals of the New York Academy of Sciences·2001
    Same author

    Survival of HIV-1 in syringes: effects of temperature during storage.

    Substance use & misuse·2000
    Same author

    Prolonged episodes of persistent asthma: A distinct clinical pattern with characteristic clinical features.

    Chest·2000

    Area of Science:

    • Pharmacology
    • Neuroscience
    • Opioid Research

    Background:

    • Opioid isomers, like levorphanol and dextrorphan, can exhibit different pharmacological properties.
    • Understanding these differences is crucial for developing targeted pain management therapies.
    • Previous research suggests stereoisomers of drugs may have distinct central nervous system (CNS) effects.

    Purpose of the Study:

    • To compare the potency and tolerance development of levorphanol and dextrorphan.
    • To investigate the hypothesis that (+)-isomers of opioids produce pharmacologically distinct CNS effects.

    Main Methods:

    • Male Sprague Dawley rats were used to assess the effects of levorphanol and dextrorphan on food-reinforced fixed ratio 15 responding.
    • Chronic administration of dextrorphan (100 mg/kg, i.p.; every 8 h) was employed to induce tolerance.

    Related Experiment Videos

  • Dose-effect curves were generated to quantify potency and tolerance.

    • Main Results:

    • Levorphanol was found to be 20 times more potent than dextrorphan in reducing responding.
    • Chronic dextrorphan administration led to a threefold rightward shift in its dose-effect curve, indicating tolerance.
    • No tolerance developed to the effects of levorphanol, even with chronic administration.

    Conclusions:

    • The distinct effects of levorphanol and dextrorphan, particularly regarding tolerance development, support the hypothesis of isomer-specific CNS actions.
    • Opioid isomers possess unique pharmacological profiles.
    • These findings have implications for understanding opioid mechanisms and developing novel analgesics.